Hi everyone, I'm relatively new to microcontrollers so hopefully this is just a simple question.

I've been messing with the audio codec examples from the ASF documentation and trying to use it in my own code. However, when I'm debugging it (SAM-ICE), some variables are optimized out and not assigned a real value. Whereas if I just run the ASF example by itself, the same variables are not optimized out. This is a problem because it is stalling my program (one while loop can never exit because of this error).

So what does optimized out mean? If I got it right, it means that the compiler has deemed it unnecessary/not needed for runtime. Is the optimized out message really the issue or something more rooted in my own code? I've imported most of the TWI code from the ASF example (leaving the codec and SSC the only thing I programmed, but only the codec is involved with the TWI part that stalls).

EDIT: Using Atmel Studio 6
EDIT2: I think it'd also be important to write that I'm using 81% of the memory. Is that safe?